Australian Moth Class Association

Can the four members who voted for Doug's Peoples Foiler please post some explanations for their votes. Doug L is using this forum as a vote of confidence in his off beat ideas:
http://boatdesign.net/forums/showthread ... 09&page=33
He really does not need to be encouraged.

Oh no he didn't Lavern!

I was taking the piss Doug!

LOL

Thanks Bruce,
This is all we need.

Doug has inspired me though. After reading through his calc's on 70 different forums, I last night placed a set of MONOFOILING, BI-FOILING, QUADROOOPLE- FOILING foils to our OVEN.

Dead set, cooked the 2kg pork to perfection in only 15minutes (from frozen). 300% quicker than normal.

I shall call it "THE PEOPLES OVEN".

Sorry Phil

I get the impression that there was a lot of experimentation in Australia on different foil configurations but not much written about it. I am not saying that all projects should be a huge ego trip ( http://www.culnane.net/dc/moth/frame.js ... /index.jsp ), but I for one would love to read about, and see pictures of, some of the ideas that have been tried. Maybe I just missed out on this stage when it happened

Maybe we are done with major foil development for a while but there is plenty other parts of the boat to look at and all items are connected. I think that the system as a whole needs to be considered. So I do not think we are done with hydrofoil development, but I for one can not think of a radical new system that has much chance of out performing the present standard.

Unless..:

Surface piercing foils on the wings seam to be the only other workable solution but these are banned and I am not sure if they would be faster...? Maybe we should un-ban them...?

If we did and someone could find a way to switch off the windward one then there would be a huge righting moment gain. That is something that could be an real performance boost. Then we would need to power up the rigs as much a possible and loose weight. We do upwind downwind courses (mostly). With the wing mounted foils downwind you would have a lots of area so you could go deep and stay on the foils. Upwind you would have loads of righting moment if you can switch of the windward foil. This foil is under you bum so a mechanical leaver thing would not be too hard to do.

So un-banning wing mounted foils and electronic systems or simply learning to sail the boats we have are my tips for major performance gains. However I am with Bruce at the moment:

"Personally I will be focusing on building a new hull and then boat setup, configuration and foiling experience before I contemplate a new foil design. "

All the best,

Doug Culnane

Doug,

most of the oz foil developments have been publicised in one way or another - ian ward's bifoiler was developed around about the same time as windrush and on the prowl first got their surface piercing foils. And before that was andy patterson's axeman foiler in the UK. I am also aware of an early fat skiff in adelaide in the late 70s/early 80s with a winged centreboard and rudder - it flew once before the foils disintegrated.

The surface piercing foils were found to be considerably slower in pre-foiling conditions and took a bit longer to get up, but once up were fairly stable in terms of fore/aft trim, but were shockers when it came to heel. According to reports, you had to sail them very flat, you couldn't make use of windward heel, as it would cause the leward foil to come out and the windward foil would dig in - more often than not resulting in a mining expedition (rapid nosedive).

Also there have been some other wand experiments - the centreboard mounted wand is something that I still think is worth looking into more - john illet and doink had them set up at the black rock worlds... I think that having the centreboard and wand together would make converting non-foilers into foilers significantly easier, simply because it relocates most of the moving parts into 1 component, albeit a more complex one.

I'm with bruce though - I'm getting a new hull (similar to bruce's) with a set of Illet foils and using a reasonably good (probably will need a new sail soon though) rig and plan on getting as much foiling experience as I can before I contemplate crazy new ideas. Ultimately I think that speed comes from getting a good setup and then getting your head out of the boat. If you aren't looking around for shifts, gusts, waves etc. you really can't make the absolute most of the conditions.

Phil, that whole paragraph about electronic controls sounds exactly like some of the arguments touted by anti-hydrofoil mothies when they were being developed! Now look where moths are.

Tell me again how much a pair of professionally built hydrofoils cost? To be fair, what is the difference in price between standard centreboard and rudder and a set of hydrofoils?

The only difference we have here is that hydrofoils weren't banned before development started (although some of the early foil styles were eventually banned), whereas electronic controls are banned before development has started.

And it will start (and probably has started), it is the next logical progression in control systems, banned or not. It will just be an underground development that probably won't get much race time until it is accepted.

btw, it's not hard to waterproof electronics in a boat, just look at all the model boats around the world.

My point is that it should be allowed and encouraged to develop underground. Maybe when it is a mature technology it can be accepted into the greater moth community.

Hi dudes, lots of intersting stuff here.

Re: electronic devices etc, the matter was debated by those eligible to debate / vote on it just on 3 years ago. Without going into the details, (Phil Stevo would be better on that)machines that were not operated by the effect of wind, water or the sailor's own kinetic energy are effectively banned by ISAF (except for big boring maxi's that need engines in order to 'sail'!! (Did I miss something about the term sailing!) (Canting Keels etc).

What we should all remember is that Moths can do what the rules allow, and that only. That is what a developement class is, developements within the rules. We regulalry get pushes for 16 foot hulls, and 9 or 10 sq metre sails, but the rules prohibit this. The whole hydrofoil 'debate' of some years back was to my mind off track, as centreline foils (unafoilers etc) were always legal under the 1972 rules when the Class became international. Wing mounted foils were not, and when the rule was tested, this was confirmed. (That is why they are banned - tight tape test etc). Yes, there have been 2 big decisions in Moths in the last 80 years, but they concerned the standardising of the two hemispheres when the class went international. (Using the old language 7 foot 4 and a half inches beam which mainly equated to wings, and the adoption of a standard 86 squre foot sail area (as opposed to the 80 sq foot sail being used in half the world at that time).

As designers, we are given some basic parametres, told what is specfically excluded, and off we go from there. One designs etc have 'closed rules' which in effect tell you what you can have, not what you cannot have. Our open rules, effectively only tell you what you cannot have. There is no rule agaist building a half or two third sized moth. It's just that it wouldn't be as fast. Whereas, you can't have a half sixed Heron etc

The foil debate of 5 years back which is being touted as an example of progressive decisione etc, was nothing of the sort. Current foils (as I said above) would have measured in, in 1972, 1982, 1992 and 2002. The resistance was to the concept - which as I publically stated at the time was a concept (as being legal under the rules) the Class had to embrace, or become a 'restricted developemnt class like NS 14's etc, which to my mind, would have ended the class. The only progressive decsion was to allow the rules to function as written, and thus the class to remain true to it's charter.

Based on some of the above posts, I am unsure as to why no one has suggested a speed board with a jet engine for lighter days!

P.S. Emmo, it was Cheese (Glen Oldfield) at Melbourne (not James Mc) who had the rear C board trailing wand. He developed and used that system which John Illett also used for that Regatta.

In good faith... Date's Up.

Nick,
I know about RC boats, I race RMs too, and I have at home two $300 winches, two $100 receivers and several servos, all water affected and in a box of other buggered junk. Most other RC sailors have a similar collection. I know a few people with their GPS in a similar state.

I also know that none of this relatively cheap equipment would be of any use , or have anywhere near enough power to do what we want of our foil control systems.

Hence my estimate of $5000 for a commercial functioning foil control system once one of your phantoms develop it. But I can not afford to have too many of these in the junk box with my winches.

If we were to adopt electronics why not extend the envelope and allow full gyroscopic stabilisation, gps navigation, oponent tracking, automatic sheeting, logic download from one of the tactical games and then we will all be able to watch the races from the bar without getting our feet wet.

If we get that far, then there is always something really boring like golf if you still need the exercise.

oops... my bad. either way, I think it is something that might be worth refining - or did cheese/john simply find out that it doesn't work as well as the separate wand?

I considered the trailing edge wand idea, but I think that one of the main problems is that it doesn't have a chance to adjust for waves before they hit the foil. One advantage they would have is that they would not reduce lift during takeoff which the current setups do. Maybe John et. al. can share their experiences?

I am trying to decide what the best wand setup is at the moment, and I can't see any real reason to not go with a prowler style setup again. The bladerider and mistress are really neat how they approach the wand, and cable but both methods add weight and opportunity to introduce leaks.

I am also keen to know what will happen to a Mistress if there is a problem with the mechanisim in the bow of the boat.

Maybe Phil can be persuaded to provide a history lesson on what he has tried over the years.

Phil's phoiling history:
1. Chainsaw 2003. Rudder and foil under bow, with manual incidence control. 1.2m main foil on fin complete with dihedral but no flap. rudder controlled by lines from conventional rudder box. One day trial. Foiled briefly, up and crash. Could not tack it, spent lots of time in stays.
2. As above plus std rudder in aft rudder box. did not foil any better, but I could tack sometimes, when the front rudder did not jamb off centre. Slow in the water and too high when foiling.
3. Tried the trailing edge wands on both fin and rudder, poor mechanical linkage meant it never did anything properly. discarded.
4. Cut down main foil to about 800 span. Made a 600 T for rudder, no flaps no control. Tossed bow rudder into back of shed. Went fast sometimes. Went pretty well in sub foiling conditions but crashed a lot when foiling. Started going fast enough to begin tearing Ts of fin or rudder. lost a few in Botany Bay.
5. Chainsaw 94. Conceeded a wand was needed. made new foils with flaps, plus full tilting CB for manual incidence control. Tried manual rudder flap control. Tried auto flap control on both flaps via a self trimming tail. Never sorted and discared at Black Rock nationals, wasnever going to sort it out in those waves anyway. Talked a lot to John Ilett at Black Rock and he gave me a lot of useful info on molds and foil construction. sailed without foils for rest of the year .
6. Tried a bow rudder again, two rudders, no centreboard. trailing edge wand on bow rudder. Showed potential, sticky steering, some weird characteristics.
7. Mid 2005. Bought Hungry Tiger Hull and made a mold for foils. Copied all of John's ideas and some of his techniques. Still using this gear and learning all the time from others , gradually going faster, safer, and having more fun.
8. Chainsaw remnants rebuilt with unstayed rig but foils same as Tiger.
9. Both boats now have prototype/reject Bladerider rudders and rudder foils.
And if I build again my experiments will be with everything except the basic foil configureation because I have found from the above saga that John Ilett's system works best of all these options.

Phil S

Reading and salivating, tx guys. I admit I have been drooling on the diamond foil pages too
I'm not sure if Berthold Neutze or Christian Kirchner from Germany are reading this. They could clear us up on the Unifoiler: http://www.mothfoil.com/

I believe this didn't work as well, and Christians boat with foils got sold as a lowrider in Germany.

Greetings,

Koos

I don't consider any of those points removed from the concept of a development sailing dinghy. If you can invent a system like that and make it work on a moth imagine the implications for the rest of the marine industry gyroscopic stabilisation for instance, imagine a sailing boat without ballast, just a gyroscope. It would be ideal for a luxury sailing boat for the reef. (my dynamics on gyroscopes is not quite up to scratch and i believe this is not realistic for this application or a moth but thats beside the point).


Phil, perhaps what you are really proposing is a cap on the amount of money you want people to spend on their boats, not the technology itself.

In which case it is not a good argument for why we should restrict this technology in a development environment.





I'm sure some people enjoy golf....

Another area that I think will evolve is centreboard case position.

I am 100% convinced that the main reason I couldn't get Virtual Reality to foil with any type of control is because the foil was lifting in the back half of the boat, due to a combination of my straight foil and having the centreboard case in a position based on the the "fat skiff" days. So when I put 10deg of attack on the CB foil and was hanging off the back to overcome this problem, volia, extreme amounts of lift, NO height control and extreme crashes from full height once the CB foil ventilated.

Rohan & John Ilett tried moving the case forwards for Garda on the Prowler Mk III, then discarded the idea. Mark Thorpe moved the mast and CB forwards on RTFM which Scott Babagge used to good effect coming second in the 2005-06 Nationals at Sunshine.

A converted HT with John's foils has the CL of the CB foil at approx 50% (halfway from the bow to the stern). I think that moving the case forward so the CB's CL is at ~45-42% should give some improved foiling liftoff and stability, and shouldn't effect the "sailing" balance of the boat too much.

I wonder where the Bladerider mast and CB are? I am guessing that they are in the same position as the Prowler and HT.